Electrical signaling



Dec. 13, 1932. M. L HASELTON ELECTRICAL SIGNALIHG Original'Filed Jan. 6, 1928 8 Sheets-Sheet 1 MEfeToN L. HASEL 70N WW. 77%;1 Z

. ATTORNEYS Dem 13, 1932, M. l.. HAsELToN z 1,890,876

' ELECTRICAL lSIGNALING original Filed Jan. 6, 192s a Sheets-sheet 2 ATTORNEYJ' A D. 13, `1932. M. L. HAsELToN 1,890,875

ELECTRICAL SIGNALING y Original Filed Jan. 6, 1928 8 Shouts-'Sheet 3 IN1/imm W10/Y L mmm/v 'Mmmm Dec. 13, 1932. M. L. HAsr-:LTON

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y M. HAsEL'roN ELECTRICAL SI'GNALING Original Filed Jan. 6, 1928 8 Sh'Qqts-Sheet 5 INVENTOR. MlPI/VZ. HASHTN /wwg *im ATTORNEY;

M. L. HASELTON `ELECTRICAL SIGNALING Original Filed Jan. 6, 1928 Dee. 13, 1932.

8 Sheets-Sheet 6 Arme/vm Dec. 13,1932. M. l.. HAsELToN ELECTRICAL SIGNALIHG Original Filed Jan. 6. 1928 e slum-sheet 7' I II 'EA/TOR. MZQTON L msizm/ ATTORNEW Dec. 13, 1932. M. L. HAsELToN ELECTRICAL SIGNALING origial Filed Jan.

e, 19za a spans-sheet a A gl SAQN ATTO/QNWY MERTON L. IEASELTON, OF RYE, NEW YORK, ASSIGNOR, BY' MIBNE ASSIGNMENTS, TQ.

r*Patented Dec. 13, 1932 UNITED s'mlrzs PATENT-OFFICE 'man 'rnLnREcfIsrEr-t conronArIoN, or NEW YORK, N. Y., A ooRronATroN or DELA- WARE ELECTRICAL sIeN-ALING Application led January 6, 1928, Serial No. 244,873. Renewed Hay 6, 1,932.

This invention relates l'to electrical signaling and more particularly to signaling apparatus and methods wherebydistinctive current variations representative of certain information may be transmitted from acentral point or points to one or more receiving stations at which the information is to be displayed'or posted or otherwise made available for use.

The invention according to one of its phases, although, not restricted thereto, is particularly adaptable to the transmission of varying stock `or commodity price quotations from a central point such as a stock exchange, to a plurality of brokers offices, at each of which, quotations of stocks which are there of particular interest may be automatically posted on a bulletin board, the information being preferably made available, generally speaking, in the same arrangement as with the conventional types of manually attended lstock boards, or black boards .as heretofore used. However, with the appay ratus of this invention thelposting of quotations may be accomplished with greater rapidity and accuracy than with stock boards which are manually attended and in addition a substantial saving of laboris made possible since the equipment for numerous brokers may be operated from the central point by a single operator or group of operators.

,The objects of my invention include the provision of apparatus of the above indicated class which will be adaptable with a wide degree of flexibility to various operating conditions and which will be. accurate, rapid and dependable in operation.

Further and more specific objectsLfeatures -and advantages will `clearly appear from the following description taken in connection with the accompanying drawings and claims whichiorm a part of. this specification.

r1`he invention comprises the novel signaling methods, features, circuit arrangements,

5 and combinations of `circuits and parts as hereinafter described, but by Way of example only, as illustrative of certain preferred embodiments of the invention.

In the drawin s Fig. 1, which extends over sheets numbere one, two and three, comprises a schematic diagram of the circuit arrangements, comprising oneembodiment of the invention.

Fig. 2 is a perspective view showing somewhat schematically the operating parts and associated electrical connections of selecting mechanism such as may be used in the circuit arrangements of Fig. 1;

Fig. 3 illustrates a supplementary selecting. device which may he used in connection with the mechanism of Fig. 2;

Fig. 4 illustrates an arrangement of conacts such as may be used in the devide of Fig. 5 is a diagram of certain electrical connections running from the device of Fi 3;

Fig. 6 schematically illustrates one' orm of transmitting circuit arrangement which may be utilized in connection with the circuits of Fig. 1;`

Fig. 7 illustrates one example of transmit- I ting device which may be used in connection with this invention;

. Fig. 8 'shows a section of transmitting tape having distinctively arranged perforations representative of quotations of various items, I

the perforations being arranged to cooperate with the mechanism of Fig. 7 to transmit the necessary current variations to actuate the apparatus; f

Fig. 9 illustrates one example of a group of indicator units such as may be used for one quotation of four digits g,

Fig. 1( isa sectional view of an indicator taken substantially along line 10--10 of Fig. 9; 2

Fig. 11 is a wiring diagram supplementing l that of Fig. 1; f

Fig. 12 shows a modicationfof the circuit arrangements of Fig. 1 ;A

Fig. 13 shows the details of a modified form of circuit arrangement involving the invention in one of its phases. y

With the conventional forms of manually attended brokers boards, provision is ordinarily made for posting the quotations of numerous stocks, commodities, or other items', each quotation generally comprising four digits, namely, the hundreds, tens, units and a fraction value. The brokers customers Vare generally desirous of' knowing the openf 6high,lovv, and last quotations tor each stock or item, and accordingly it is customary to provide space for such quotations, that is, 'for a total of 'i6 digits in all for posting the quotations oit a single stock or other such item. lit has heretofore been the custom oi brokers to post quotations for a number ci stocks in the neighborhood oi one hundred or more, although a much larger multitude ot stocks and commodities are dealt in on the various exchanges of the -United States. However, each broker is ordinarily particularly interested in posting only the quotations oi a chosen list oi stocks and commodities, such list including a limited number ot items which are oit universal interest and also a number of more or less inactive stocks or stocks oit' lesser importance which are dealt in by the brokers customers, or stocks to which the broker desires to direct particular attention. in order that the broker need not have a multitude of indicators providing for the quoting oi all of the large number of listed stocks, a method and apparatus such as disclosed in the patent to Robert L. Deine, No. 1,658,516, dated February 7, 199.8, may be utilized whereby each broker requires only a relatively limited number otindicating devices which will more conveniently it into the limited space such as is ordinarily availl able in brokers otiices in the financial districts. Such indicators are arranged to be interchangeably connected to a terminal board so as to post any chosen small number of stocks which the broker may select from the large list Jfor which service may be supplied to him bly the use of the apparatus oi this invention. In order to electrically control the Vindicators at a plurality of brokers7 offices from a distant point it is economically impracticable with the prevailing line wire costs, to provide separate line connections for giving quotation service 'for each of the multitude oi listed stocks. Accordingly, it is desirable to provide means for sending current variations representative oi the quotations of numerous stocks over a relatively small number of line wires., and to provide selecting means at each brokers oiiice to identify the quotations oi particular stocks and to prepare the corresponding indicators for energization. However, in thus reducing the number otline wires to a relatively small number, special attention must be directed to the necessary rapidity of operation of the indicators. Taking into the account the reasonable future requirements, provision should now be made in an apparatus of this class for sending quotations for more than a thousand diderent stocks or items, each of which must be individually identified by the selecting means. After such identification four digit indicators preferably should be actuated to show a particular quotamadera tion, and in the event that the highls or dow quotations are to be simultaneously set up then as many as eight digit indicators may be actuated. i/V ith stock market transactions conducted at the present rate, provision must be made 'for transmitting :trom 30 to 60 new quotations per minute. Such speed oi operation of a multitude oita indicators at didlerent omces, but all selected and actuated in a dependable manner over a relatively small number oit line wires, necessarily requires novel circuit arrangements which have no counterpart in other classes of signaling apparatus.

According to my invention ll have found it desirable to provide 'tor each unit ot signaling apparatus tour line wires, or equivalent impulse channels which are associated with a common ground return circuit, and may be utilized iirst to simultaneously operate 'tour selecting devices for choosing one particular stock to be quoted. rEhereatter the same iour line wires or impulse channels may be conveniently utilized to simultaneously, but independently actuate the tour digit indicators ot a particular quotation, that is, for example, the hundreds, tens, units, and iractional digit indicators it all of these need to be changed. Furthermore, it desired, the number of line wires may be further reduced by utilizing the Well known principles ot multipleX telegraphy whereby the current variations, in lieu of being transmitted over the tour wires or a larger number of wires, may be transmitted over a single wire with a ground return or an equavilent return wire through the use ot synchronous transmitting and receiving distributors at the sending and receiving stations. Such multiplex transmission may be found to be particularly desirable in instances Where the line wires extend between widely spread cities. Such devices as used in high speed telegraphy may be utilized for this purpose, and since the construction of the same is well understood in the art the same will not be here described. However,

one form of multiplex apparatus and arrangements for applying same, applicable to the subject matter ot this invention in certain of its phases, are disclosed in the co-pending application ot Ernest Frischknecht and Jean Abegglen, Ser. No. 258,219, tiled March 1, i928. 1

In some instances in order to provide the necessary speed of operation two sets of transmitting and receiving apparatus may be utilized, the two sets being substantially duplicates, and inthe event that the line wires or other parts of one set become injured, service may be maintained on the other set. At other times the list of items may be apportioned between the two sets.

The current variations or impulses for selecting and actuating the indicators may take either the form of positive spaced impulses, or

A H. H. Harrison in may be in the form of undulations or interthe line wires. With the particular form of selecting devices described in connection with the example of the invention here disclosed the latter method is followed, that is, the distinctive current variations comprise short interruptions or reductions in the line Wire potential. The selecting devices may be constructed with a suiiicient number of contacts so as to select not only the desired stock but also the particular quotation as the open,

high, low or last, which has to be changed, or on the other hand only a smaller number of selector contacts need be provided where the selectors merely choose the particular desired stock. According to the embodiment of my invention here described, I have provided means whereby one of the quotations, either open, high, low or last is selected merely by the polarities of the several line wires. That is, the sustained potential applied to each line wire may be relatively positive or negative in respect to the other line wires, and accordingly, numerous combinations of polarities may be obtained, suiiicient in number to readily choose between the open, high, low and last indicators, thus materially reducing the work to be done by necessary for the operation thereof.

The method ofl using a maintained line potential not only simplifies the selecting problem in this manner but also makes possible in a simple manner thepuse of an adaptation of the well known Strowger up and around selecting devices as are well known in the art of automatic telephony switching. The construction and operation of such selectors is set forth in detail, for example, by

his book entitled Automatic Telephony7 published in1924 by Longmans. Green & Co., and also by 'R. G. Kloeffier in Telephone Communication Systems, Macmillan Co., 1925,` Chapter XIV, and accordingly the constructional details of such selectors will not be here fully described, al-

as are necessary to adapt the same to my invention are hereinafter fully disclosed. Since this type of selector automatically restores itself to a normal position upon any extended interruption of the line potential, such selectors are particularly desirable for use with this invention inasmuch as such restoration to normal after each operation substantially precludes all possibility of cumulative errors or false quotations on the multitude of indicators. Furthermore, the circuits of such selections, as will be hereinafter further explained may be adapted to effect restoration to a zero or normal position, such indicator units as have been selected, and to connect such units to operating busses for actuation immediately upon completion of the selecting and restoration steps.

Robert L. Daine and the desired characters may the selecting devices and the time The circuit arrangements of Fig. 1 for the embodiment of the invention there shown will now be described together with the functions and construction of the various elements of the apparatus.

Indicatz'ng units The indicating units per se may be arranged in sectional cabinets or otherwise, one desirable construction and arrangement being illustrated in the copending application of Ren Guy, Serial Number 246,474, led January 13, 1928. Each of the digit indicators as explained in the said application may comprise a rotatable drum having on its periphery a series of characters, such as the figures one to nine, a blank space and zero, or various fraction characters, such drums being rotatable step-by-step in one direction by an electromagnet whereby be exhibited at the frontof the board. Such indicators may be restored to zero or normal either by further step-by-step rotation, or if desired they may be more q ickly restored to normal by suitable sprin releasable by the operation of a trip magnett The constructional features of a group of such indicators are schematically shown in scribed.,

The rotatable drums bearing the digits are indicated at 20 and may be rotatably mounted in respect to a' shaft 21 which in turn may be mounted in bearings 22 and 23. Each of the drums 20 may be provided with an operating star wheel as at 24 ixed against rotation in respect to the drum as by a slot and pin connection 25. The star wheels 24 may by the use of collars as shown at 24 be fixed against longitudinal movement in respect to the shaft 21 but are free for rotational movements in respect thereto, Vand are also free for only a limited longitudinal movement in respect to the drums 2O by reason of the connections 25. Each of the star wheels 24 may cooperate .with an actuating fork as at 26 pivoted at 27 and; having an armature 28 acted upon by actuating magnets as at 29, whereby impulsive energization of the magnets will cause the corresponding drums to be advanced step-by-step in one direction and against the action of spiral springs as in 30, one of which is provided within each indicator drum. One end of the spring 30 may be suitably connected to the indicator wheel as indicated at 30a Figs. 9 and 10, and the other end may be anchored to a sta.- tionary indicator guide 301) which, if desired, may be secured `to the casing or to any stationary part to hold the indicator against lateral displacement as the shaft 21 and ratchet discs 24 are shifted to the right in Fig. 9. The digit indicators may thus be mounted in groups, one group for each quotation comprising four units which are individually and simultaneously operative by the various electromagnets 29. So long as the star wheels 2t are in engagement with the forks 26, the springs 30 are precluded from acting to restore the drums to normal. However, when the star wheels are taken out of engagement with their vtorlrs, the springs are tree to immediately restore their respective drums to a normal setting. ln order to move'tlie star wheels out of engagement with the forks, it is merely necessary to move the shaft 21 longitudinally through a short distance and this may be accomplished by a tripping magnet as at 3l, acting through an armature 32 connected to the shaft in a manner obvious from the drawings. Accordingly when the tripping magnet 31 is energized, the ourindicating drums for one quotation may be at once simultaneously restored to normal in prepa` ration for a new setting.

llt may be here noted that such restoration to normal is particularly advantageous with this apparatus, inasmuch as cumulative errors in succeeding quotations are thereby avoided, and furthermore the operator in controlling the system need not take the necessary time to examine the setting tor the previous quotation before taking the necessary steps to post the new quotation. Subtraction or adding of quotation values and the possibility of errors in so doing are thereby eliminated, with a considerable saving of time. @ther suitable forms of digit indicators are disclosed and claimed in my copending ap plication, Serial Number 276,883, tiled May 11, 1928. And other indicating units of this general type are disclosed in the patent to Farvarger, 1,787,629, dated January G, 1931.

In Fig. 1, sheet three, it will be noted that the actuating magnets 29 are schematically indicated in sub-groups of four, such subgroups also being arranged in groups of four so as to provide for the indicators showing the open, high,.low and last quotations for each stock. Also in this figure one of the tripping magnets 31 will be noted adjacent to each of the sub-groups of four. All of the magnet coils 29 and 31 as shown may have one terminal connected to a common return bus as at 33 which in turn may be grounded at 34 through a source of current 35. The opposite terminals may be provided with individual lead wires as at 36. The lead wires 36 for each stock may extend to a twenty-one contact relay as at 37, there being twenty magnet coils including the actuation coils and tripping coils, requiring twenty lead Wires for each stock or other item, an additional lead wire 38 being provided, if desired, to energize an indicating lamp 39 which may be lighted during actuation of the indicators for the particular stock chosen. Such lamps serve to attract attention to the part of the brokers board where quotation changes are taking place. The relays 37 serve to connect the various groups of lead wires `whenever' a relay 37 raconte 36 respectively to groups ot open, high, low and last9 control busses 40, d1, 42, and 43. Relays 37 are normally open, but upon the choosing oit a particular stock, by the selecting devices hereinafter described, the corresponding relay 37 `will be actuated by reason of the energization of the relay magnets as at44. The terminals of the relay magnets 44 may be connected to selector cir* cuits as indicated at 45. rlhe relays 37 when actuated also serve to connect the lead wires 38 of the lamps 39 to a common lamp bus 46 which may be grounded as shown. @ne lamp terminal is therefore grounded whenever the corresponding relay is actuated, the other lamp terminal as shown may be connected with the common return bus 33. Therefore is actuated, the battery 35 acting through the ground 3d will cause the corresponding lamp 39 to be lighted.

Interchangeable selector circuit arrangement its above stated, in the aforementioned patent of Robert la. lDaine, means are disclosed whereby a limited number ot digit indicators may be provided with interchangeable connections cooperating with the much larger number of terminals identified with a multitude of stocks or other items. 'lhe use ot such an arrangement is here illustrated in the drawings somewhat schematically at the upper part of Fig. 1, sheet two.

The selector circuits 45 above referred to, may each be provided with quick-detachable plugs as at 47. lt will be understood that although only i'ive of the selector circuits 45 and indicators for four stocks are shown for simplicity on sheet three, a complete assembly of the apparatus would embody a number much greater than four. lf desired the circuit wires 45 may be extended to a c0nsiderable distance away from the indicator board, as for example to a special compartment or closet in the brokers establishment. In such a separate compartment a switch board as at 48 may be provided with a number of terminal jacks 49 equal to or substantially equal to the total number of listed stocks or commodities for which quotation service is transmitted. The switch board 48 may be provided with a plurality of vertically extending busses 50 and also a plurality of horizontally extending busses as at 51. llt will be noted that one of the terminal jacks 49 is provided at the intersection of each vertical bus with each horizontal bus. As will be hereinafter described, one set of selecting devices may be provided to choose any one of the numerous vertical busses, whereas another and separate set of selecting devices may be provided to choose any one of the horizontal busses, such groups of busses respectively beingelectrically connected to thc selecting devices by multi-Wire cables as at 52 and 53. lAccordingly the two sets of selectors 60 plained, carries choose any desired one of the terminal jacks 49 to the exclusion of the others. Although but a relatively small number of vertical and horizontal busses 50 and 51 are indicated in the drawings, as many as one hundred vertical busses and one hun- -dred horizontal busses may be conveniently installed and controlled by suitable selectors such as hereinafter may conjointly act to described. Such a number of busses, it will lbe observed will provide for a total of ten thousand terminal jacks, or in other words provision may thus be made for ten thousand stocks or other items. On the other hand, with the plug and jack arrangement only a relatively limited number of indicators and indicator circuits equal to a small number of stocks chosen for posting by each broker need be provided, and yet the plugs and jacks may be made interchangeable to afford great flexibility of service. Also according to my invention, although the indicator units for each stock may require numerous lead wires and busses, connections to the interchangeable plugs require no more than two wires, and accordingly the multitude of terminal jacks may be mounted in a relatively small space and the plugs may be of a conventional size and easy to manipulate. It will be understood that whenever a particular terminal jack 49 is selected and energized, providing there is a plug inserted in such jack, the corresponding relay 37 will be energized, whereupon all o the indicator units for the stock or item corresponding to such relay will be connected to the actuating busses 40, 41, 42 and 43.

f Selector mechanism As above noted, four line wires may conveniently be utilized and'these are designated by the characters L1, L2, L3 and L4 (see Fig. 1, Sheet one) The selector mechanism as shown on sheet one may conveniently be grouped into four parts, each part being respectively controlled by one of said line wires. 4These parts of the selector mechanism may be designated respectively as the thousands, hundreds, tens and units selectors.v .The thousands and hundred selectors are arranged to select over the multi-wire cable 52 any desired one of the vertical busses 50, whereas the tens and units selectors are arranged to select, over the cable 53, any desired one of the horizontal busses 51. In addition the thousands selecting mechanism, after completing its selecting action serves to bring the line wire L1 into operative relationship withan indicator operating bus B1 which bus as will hereinafter be further eX- the impulsesfor Acontrolling digitindicator of the quota- Thehundreds selector mechaafter completing its selecting bring the line wire L2 into the hundreds tion selected. nism serves, operations to 65 operative relationship with indicator opert dicator operating the circuit ating bus B2 over which the tens digit indicaters are actuated. The tens selector mechanism after completing its selecting function, brings the line wire L3 into operative relationship with indicator operating bus B3, over which the control of the units digit indicators is accomplished. Lastly, the umts selector `mechanism, after completing its selecting operations serves wire L4 into operative relationship with inbus B4, over which the fraction digit indicators are actuated as will hereinafter'be more fully explained.

The tens selector mechanism in addition, after completing its selecting operations, opens a bus R after the return to normal of the particular lindicator units selected has been effected.

The moving parts of a selecting device such as may be used for the thousands an tens selectors are illustrated diagrammatically in Fig. 2. A rotatable and vertically movable shaft is indicated at 54. This sha is normally urged by a spring 55 toward a position of rest in the direction indicated y the arrow. The shaft is also normally brought to rest by gravity in its lowermost position. A wiper having two contact `arms 56 and 57 is secured to the lower end of the shaft 54 and is designed to. engage with the chosen pair of a group of one hundred pairs vof selector circuit contacts, each air f comprising a control contact as at 58 an an indicator contact as at 59 for engaging, respectively, the control wiper 56 and the indicator circuit wiper 57. `It will be noted that the contacts 58 and 59 may be arranged in the customary cylindrically shaped bank, ten vertical tiers of contact pairs being provided, each tier having ten pairs of contacts. Each of the indicator contacts 59, respectively is brought into electrical connection by the lead wires-52 with one of the vertically extending terminal board busses 5G. (See Sheet 2.) The manner in which such connections may be made is more fully shown in Fig. 11, which will be hereinafter described in lfurther detail. The control contacts 58, respectively, are electrically connected through the lead wires 60to proper corresponding contacts 61 located on the hundreds selector device. Through the connections 60 the thousands selector functions as a major selector and the hundreds selector as a minor selector, and as will be further explained, the tens selectors and units selectors,respective ly. bear the ,same relationship.

to bring the line i Reverting to the mechanical features of i aendern shaft. lhe arm 64 is also provided with a switch operating branch arm 67 so that whenever the magnets 62 are energized contacts 68 and 69 are separated so as to break any circuit there-between. The step by step vertical movement of the shaft is etiected by the action ot the vertical magnets 7 0, which act through an armature 7l. The arm 72 carries a spring pressed pawl 7 3, which is are ranged to .engage the ratchet portion 74 oit the shaft so as to move the shaft upwardly whenever the vertical magnets are in-- pulsively energized.

The shaft 54 may be provided with an enlarged portion 75, which, when the shaft is in its lowermost and normal position, engages a switch operating bell crank 76. The bell crank 76 serves to operate two sets of switch contacts 77 and 78, which contacts correspond to those known as olf normal switches in the machine switching art.. rlthese two switches may be conn-ected by an insulating piece 79 so that thetwo operate together, and whenever the shaft 54 is in its lowermost or normal position these two` switches are both in open circuit position but as soon as the vertical magnets raise the shaft as much as one step yupwardly both switches 77 and 78 move to circuit closing positions. A double dog 80 may be pivotally mounted in a suitable manner such as indicated and has two arms 81 and 82, respectively, tor engaging the toothed portions 66 and 74 of the shaft 54 so as to follow up the pawls 65 and 73, respectively, and retain the shaft temporarily in the angular and vertical position into which it is brought by the rotating and vertical magnets, respectively. The double dog 80, however, is under the cont-rol of the release magnet 83, having an armature 84. The armature 84 is operatively linked as at 85 with the dog 80 in a manner whereby energization of the magnet 83 effects the release of the double dog, permitting the shaft 54 to rotate to normal angular position and to drop into normal vertical position, the pawls 65and 7 3 being normally held out of contact with the shatt.

Features of construction of the selector ydevice ot Fig. 2 which are notl herein specifically or fully shown and described may be providedaccording to the practice followed in the telephone switching art and as more fully settorth in the textbooks above mentioned.

Referring to the circuit arrangements shown in lFig. 1, Sheet l, and particularly' the thousands selector, the various magnets and switching parts, the functions of which are abofe described, are there indicated by corresponding reference numerals. In addition, aplurality of relays 86, 87, 88, 89 and 96 may be associated with this selecting device. Certain of these relays are quick acting, both at the pick up and at the release thereot". 'llhe armatures of others are provided with copper slugs in a manner well known in the art so as to render the relays slow to operate. 'lhese may be distinguished by the symbols as set forth on Sheet l. is well known, a copper slug on the relay magnet core may beplaced on the end nearest the armature to eltect a delayed pick up, conversely, if a slug is placed on the magnet core end opposite from the armature, (the cheel end), the pick up action may be rapid but the release action will be delayed. rlihese two types it will be noted have been symbolically distinguished in llig. l by the use of cross hatched and black armature portions.

rllhe operation of the circuits of the thousands selector will no-w be described. This selector, as above stated, is operated over line wire Ll, while its rotary motion is controlled by the hundreds selector, which is actuated over line wire L2. As above explained in connection with Fig. 2, the vertical magnets 70v andthe rotary magnets 62, respectively, are designed to `bring the switch wiper' arms 56 and 57 first to the proper vertical position and then to the proper angular position, so that the wipers will engage the desired pair ot contacts 58 and 59. lt the line wire lil' is energized with a`maintained potential, for example, titty volts, relay 87 picks up and causes the relay 88 to be energized through a circuit, including the ground and battery as indicated, the magnet ot relay 88, the make spring of relay 87 to ground. Relay 88 thereupon prepares but does not complete an additional circuit for the reception ot subsequent impulses. This circuit comprises the ground and make spring ot relay 87, the make spring at 91 of relay 86, the make spring at 92 of relay 88, the magnet coil of series relay 89, the coil of vertical stepping magnet 70 to battery and ground.

it the transmitting station current v-ariations may be sent out in the torna oit undulations or drops in the potential maintained over the line wires, but for the purposes of operating a selecting device such drops ot potential are of such short duration that the slow to release relays, as at 88 and 89, are unaected thereby. The first ot such impulses causes the relay 87 to release momentarily, thus closing the circuit last described above, causing the series relay 89 to be energized and also the vertical stepping magnetV 70 which advances contact wipers 56 and 57 upwardly one step. Concurrently, the relay 89 picks up, and also the oft normal switches 77 and 78 become closed, the switch 78 closing a circuit through relay which picks up.

The circuit of relay 90 comprises ground, battery, make spring 93 of relay 88, magnet coil ot relay 86, together with a non-inductive resistance 94 in parallel therewith, break `98 of relay completion of the spring 95 of relay 86, switch contacts 68 and 69, 0E normal switch 78, magnet winding of lrelay 90, to ground. -It should be here noted scribed, picks up and prepares a circuit through the rotating magnets 62, which, however, is not complete, being broken at the break contact 96 of relay 89 until such time as the last of the group of impulses is received, when, as hereinafter further explained, the relay 89 releases and completes the circuit picked up by relay 90. This circuit comprises ground battery, make spring 93 of relay 88, break spring 96 y of relay 89, make spring of relay 90, rotating magnet 62, thence to the off normal springs of the hundreds selector, which will be hereinafter further described in detail, break spring at 99 of the hundreds selector, make spring at 100 of relay 101 of the hun. dreds selector, to ground. i i

This circuit is not completed in the hundreds selector until the series of impulses onf the line wire L2 has been completed, as hereinafter explained, the circuit remaining open either at the off normal spring 97 or the break spring 98. Consequently, the rotating magnets 62 are not energized until the hundreds selectorhas completed its motion,

i and therefore the thousands selector wipers are also not rotated until such time. Upon movement of the hundreds selector, however, the rotating magnet 6 causes the thousands selector shaft to be rotated through an step, which places engagement with in the first vertical tier. ever, the vertical step by step movement of the thousands selector shaft has been completed by successive impulses acting upon the vertical magnet so that the wipers are brought into 'engagement with the Contact at the. selected level in the thousands selector. At the same time that th'e rotating magnets 62 receive the first impulse the closing circuit of relay 90 is broken by the break springs of magnet 62, that is, cont-acts 68 and 69, and thereupon relay 90 opens the holding circuit of rotating magnet 62 by breaking such circuit at the make spring of relay 90. rlihe magnet 62 therefore releases the contact 68 and in so doing again closes the circuit of relay 90 at the contacts 68 and 69.

Assuming now that there is no ground connection at the control contact 58 in tier thus engaged by the wiper 56, then relay 90 again picks up through the same circuit as formerly. Thus the rotating magnet 62 and relay 90 alternate, in picking up and releas# ing, and cause the wiper contacts 56 and 57 to the wipers 56 and 57 1n angle equivalent to one` continuously since the first be rotated until the control wiper contact 56 comes to a control contact 58, which is grounded, such grounding having been effected by the operation of the hundreds selector through one of its control contacts 61, as is hereinafter further explained in connection with Fig. 5. When the control wiper thus encounters. a grounded contact 58, the relay 86 is immediately picked up through the circuit comprising ground, battery, make spring 9 3 of relay 88, relay 86, control contact 58, circuit connections 60, one of the control contacts 61, to. ground. This same ground, through the control contacts and wipers, short circuits relay 90, which is thereby prevented from again closing the circuit through the magnet 62, thus stopping the rotary motion of the wiper` contacts56 and 57.

stantly grounded, as shown, while its other terminal becomes then grounded through the ofin normal switch 78, switch contacts 68 an 69, break spring 95, control contacts and wipers and contact 61 at the hundreds selector. c

It may be further explained that the relay 86 performs three functions, namely: first, it picks up and opens the circuitvthrough the break spring 95 as an additional precaution precluding further actuation of the rotating magnet 62 in cooperation with the relay 90; second, relay 86 causes its make spring a 91 to prepare a circuit to the first indicator operating bus designated by the character B1, such circuit being as follows,-ground, break spring of relay 87,'make spring at 2 91 of ,relay 86 to the indicator operating bus 'BL Consequently,

after the selecting operations are completed, any further short current interruptions or potential drops over the line wire L1 are transferred by the action o the relay 87 to the indicator bus B1 in the form of positive impulses, having no further effect upon the selector. Thirdly, the relay 86 when it picks up completes a circuit through its make spring at 102. the circuit comprising ground, battery, make spring 102, indicator wiper 57 and the corresponding circuit connection 52, thence to the terminal board as described in connection with Sheet 2,'this latter circuit comprising the circuit over which the chosen stock is identified on the terminal board.

During the above to release,has been closed the initial energization of the line Wire L1 as itis not responsive to short impulses. The potential is maintained with short interruptions only on the line wires and L2 from the time the selecting operations are initiated until not only the selection is completed, but the actuation of the chosen indicators is completed. Therefore the hunbeing av relay slow dreds and thousands selectors may be redescribed selecting oper? ations, it will be observed that the relay 88 ready to receive a normal.

leased merely by the removal of the potential from the line wires lul and 112. Such removal of the potential in the case of the thousands selector causes the relay 8'? to be released a sutlicient length of time to also effect the release ot the relay 88. This action establishes a circuit through the release magnet 83 as follows: ground break spring or relay 8l', to break spring at 91 otrelay 86, brealr7 spring' at 92 of relay 88, oil normal switch 77, release magnet 83, to battery and ground. The release magnet 83 when thus energized releases the double dog 80, as explained in connection with ll ig. 2, and the selector shaft 54 is rotated as above stated, by the spring 55, and also drops by gravity, to normal position. Concurrently, with the release of relay 88, relay 86 is released, as its holding circuit is broken at the break spring 93,01 relay 88. 'llhe thousands selector is therefore now further series of selecting impulses.

The hundreds selector may take the form of a simple rotary step by step switch as shown in lligs. 3 and t. This switchmay be provided with ten contacts, as at 61, positioned on an insulating support member 103 in an arcuate arrangement for cooperation with a wiper Contact member 104 rotatably mounted upon a shaft 105. Beneath the contacts 61 a pair ot segmental Contact strips 106 and 10"? are provided, insulated trom each other and arranged to cooperate respectively with wiper contacts 108 and 109, also mounted to rotate with the shaft 105. rllhe cooperating contact 106 and wiper 108 comprise the hundreds selector oil normal switch 97 hereinabove mentioned, whereas the cooperating contact 107' and wiper 10.9 comprise an oli' normal switch 110,.as indicated at the hundreds selector on Sheet 1.

The segmental contacts 106 and 107, as indicated by the dotted lines in Fig. 3, are coextensive with the arcuate group of ten contacts 61, whereby contact is made with the segments 106 and 107 whenever the switch moves trom its normal position, as shown in Fig. 3. 'llhe shaft 105 may be provided with a ratchet segment 111 engaged by an actuating pawl 112 which in turn is operated by a rotating magnet 113 having an armature 111 operatively connected to the pawl 112 in a .manner readily understood from ll ig. 3. The

rotatingr magnet 113 is thus enabled to advance the wiper contacts 104, 108 and 109 together, witha step by step movement and against the force'of the restoring spring as at 115. During such step by step movement t-he holding pawl 116 functions to prevent the spring 115 from restoring the wiper arms to However, after the selecting and actuating operations are completed in the system, a lrelease magnet 117 becomes energized, as will be hereinafter explained, which magnet retracts the holdingvpawl 116, permitting assente the spring 115 to restore the switch to neutral or normal position. I lTurt-her constructional details ot step by step switches such as that of llig. 3 may be found in chapter 2 of ll. ll'. lclarrisons boolr on Automatic Telephony above cited.

llhe operation of the electrical circuits per- 'taining to the hundreds selector will now be described. The function ot this selector' in ell'ect is to provide a storage means for the impulses sent over line wire L2, which storage is eidective until the thousands selector wiper contacts have arrived at the desired elevation in a' position ready tor angular or rotational movement. The hundreds selector thereupon controls the starting and stop ping of such rotation ot the thousands selector wiper contacts so that the same are brought into engagement with the desired pair of indicator and control contacts 58 and 59. rlhe electrical operation ot the hundreds selector is similar to the operation of the part o1 the thousands selector which accomplishes the vertical movement. lvlllhen a potential for example, 50 volts) is applied to the line wire 112, the line relay 118 is energized and picks up thereby, also causing the relay 101 to be energized over the following circuit: ground, make spring of relay 118, magnet winding of relay 101, to battery and ground. rl`he relay 101 when thus actuated prepares ut does not complete an impulsing circuit through rotating magnet 113 as follows: ground, break spring of relay 118, break spring of relay 119, make spring at 120 of relay 101, magnet coil ot relay 99, to the winding of rotating magnet 113, thence to battery and ground. Upon the occurrence of the lirst current variation, that is, a drop in voltage ot short duration occurring on the line wire L2, the line relay 118 is momentarily released, which complet-es the prepared circuit through the rotating magnet through relay 99 by reason of the closing of the break spring of the relay 118. The lrst short current variation therefore causes the rotating magnet 113 to rotate the shaft 105, and the wipers 101, 108 and 109, through an angle comprising one step. Concurrently, by reason ot such angular advances of the wipers 108and 109, the ott normal switches 97 and 110 areclosed. Since the rotating magnet circuit runs through relay 99 this relay is also energized. Since the relays 101 and 99 are of the slow releasing type, as indicated, they will remain in picked up condition while a series of current variations are being received. The succeeding current variations or impulses therefore will cause the rotating magnet 113 to advance the wipers through the desired angle to bring the wiper 104 into contact with a desired one of the contacts 61.

Vhenthis is accomplished and the series of impulses is completed the slow acting relay 99 will be released, permitting the circuit to be closed from a ground to the rotating magnet of the thousands selector as follows: ground to make spring 100 ofvrelay 101, break spring 98 of relay 99, off normal switch 97 to the rotating magnet of the thousands selector as above described. This same L2 will be transferred to the indicator operating bus B2 and have the selecting devices. The circuit to the operating bus B2'is as follows: ground, break contactnof line relay 118, make contact of relay 119, indicator operating bus B2 to the selected indicator or indicators, thence to battery and ground, as shown on Sheet 3 of Fig. 1.

rlhe construction, operation and circuit arrangements of the tens selector and units selector, respectively, are the same as of the thousands selector and hundreds selector, corresponding parts being designated with the same numerals accompanied by prime marks. llt will be understood that current variations sent over the line wires L3 and L4, respectively, serve to operate the tens and units selectors in the same manner as current variations on line wires L1 and L2 are utilized in connection with the thousands and hundreds selectors, and that the tens selector serves to establish, as above referred to, an impulsing circuit connection for indicator operating b us B3, while the units selector establishes a circuit connection for the indicator operating bus B4. The tens selector circuit `arrangement is provided with an additional relay .121

for restoration to normal of the selected indiy cators prior to actuation thereof.

1t will be noted that. this relay is interposed in the circuit running from the make contact 102 to the selected indicator contact 59', and accordingly as soon as the indicator contact 59 is selected and engaged by the indicator wiper, the relay 121l is energized. However, it will be noted that relay 121 is shown as a relay which is slow to pick up as well as slow in releasing. Accordingly, after a current is established through the chosen contact 59', the twenty-contact relay 37 corresponding to such chosen contact will have am le time for actuation before the relay 121 ic up. As soon as the twenty-contact relay 37 of the chosen stock is actuated to connect in circuit' the indicating vunits of suchstock,

through the zero break contact a current will be established restoration bush and the' no further eifect upon.

122 of relay 121. (A portion of this circuit will be hereinafter further described in connection with Sheet 2.) However, after a short interval the relay 121 will pick up, causing the zero restoration circuit to be opened at contact 122, but in the meantime the zero restoration magnets 31 will have tripped the indicating units, allowing the same to be restored to a normal position ready for reactuation over the indicator operating busses B1, B2, B3 and B4. i

Upon completion of the operation of the thousands selector, it will be noted that the contacts at 102 .serve to apply a battery and ground connection to the desired selector circuit connection 52 by way of the selected contact 59. Accordingly a battery and ground connection is thus applied to the selected vertical bus on the terminal board 48. 0n the other hand, it will be noted that upon completion of the selecting operations by the tens selector, the contact 102 serves only to apply a ground connection to the chosen selector circuit connection 53. That is, the selected horizontal terminal board bus is accordingly ounded whereby the chosen multicontact relay 37 will be provided with an energizing circuit extending from the batteryn and ground at contact 102, through the terminal board and multicontact relay, back through the terminal board and to the ground applied at contact 102. A

The circuit for rely 121 starts' from the battery at the left of the thousands selector and continues over contact 102, contacts 57, 59, line 52, one of the pair of lines 45, relay 44, the other line 45, line 53, contacts 59', 57', relay 121, and contact spring 102 to ground.

This circuit is completed after the thousands and tens selectors have completed their selection of lines 52 and 53.

0pm, high, zow, ma las Seaman 4Referring to Sheet 2, the groups of open, high, low and last busses 40, 41, 42 and 43 are each provided respectively with circuit closing relays each of srch relays having of which correspond respectively tothe circuits of the four digit indicating units and the fifth contact providing for the connection of the restoration'bus R to the selected restoration magnet 31@ That is, the hundreds, tens, units and fraction busses B1, B2, B3 and B4 may be connected by the relays 123, 124, 125 and 126, respectively, to either the open, high, low or last busses.. As has been above explained briefly, the choice as between these four groups of busses is determined by the polarity lished on the I L4. These four line wires are operating coils of three relays, at 127, 128 and 129. As shown,

of the potential initially esta four line wires L1, L2, L3 and connected lto as indicated, the line wire L1 may be connected to one coil of the relay' 123, 124, 125 and 126,'

fivecontacts, four the operator at the transmitting station.

127, the other terminal of such coil running to one coil of the relay 128 and thence to ground. llihe line wire L2 may pass through a compensating resistance 130 and thence through another coil of the relay 127 to ground. llhe line wire L3 may run through a compensating resistance 131, thence through a second coil of relay 128, vto ground. The

line wire 1A may run through a single coil of the relay 129 and thence to groun rl'he action of the relays 127, 128 and 129 is to connect a ground and battery as at 132 to any desired one ofthe circuit closing relays 123, 124, 125 and 126, respectively, through a corresponding one of the connecting wires 133, 134, 135 and 136. By such actuation of the circuit closing relays the polarities established o n the line wires determine whether the indicator operating busses B1, B2, B3 and B4 are to be connected to the open, high, low or last busses.

The manner in which the line polarities actuate the relays 127, 128 and 129 will now be further explained in connection with the tabulation shown on Sheet 2. The two windings of the relays 127 and 128 may be substantially equal and independent, as shown, whereby they may assist eachother, or substantially neutralize each other in effect, depending upon the line polarities. The relay 129 may have a single winding, its function being only to connect the battery 132 whenever the lines are energized and permitting the battery to be disconnected wherever the line wires are not energized. If desired, this relay may also be used to control battery charging equipment' so that the batteries at the receiving stations may be charged only when the line wires are energized. For these purposes the relay 129 may be provided with a pair of make spring contacts 137 and 138. The contact 137 serving to connect the battery 132 to the open, high, low and last selecting or connecting relays, whereas the contact 138 may serve to connect the battery 132 to suitable battery charging apparatus. The relays 127, 128 and 129 may be all of the slow to release type whereby they will not be responsive to selecting and indicator actuating impulses. The relays 127 and v 128 may be provided with contact actuating armatures retained by springs in one position and drawnby the relay magnets to their opposite positions, the relay 127 having a pair of armatures operating in unison, and the relay 128 havingv a single armature. The manner in `which the armatures and their contacts are operated by the various polarities of the'line wires is set forth inthe tabulation vof sheet two, which is self-explanatory and indicates the manner in which the polarities may be chosen so asy to choose either the open, high, low or last at the will of Selector' crcutz connections lteiterring to Fig... 11 it will be noted that two groups of selector contacts, each including one hundred contacts, are shown, one of. such groups being representative of the indicator operating contacts 59 of the thousands selector and the other group being representative of the indicator operating contacts 59 of the tens selector. terminal board 48 is here shown in further detail, together with the manner in which the contacts 59 and 59 may be attached thereto. The transmitting facilities, as will be hereinafter described, may preferably be pro vided with arrangements for transmitting pluralities of current variations equal in number to the corresponding selected digit. That is, assuming ,that it is desired to select a stock or item which has been given a predetermined designation such as number 1204, then over line L-1 a single current variation will be transmitted to advance the thousands selectors vertically one step. Over the line wire L 2 two current variations will betransmitted to actuate the hundreds selector, whereby the wiper on the thousands selector will be rotated two steps. Likewise tenand four current variations, respectively, will be transmitted over lines L-3 and L-l, causing the wipers on the tens selector to be elevated ten steps and rotated four steps. The result of thesevariations will be that the thousands indicator circuit wiper will engage the contact 59 bearing the miniature number 12 in Fig. 11. (The miniature numbers used in designating the contacts and terminal jacks are considerably smaller than the numerals used in designating other parts of the apparatus and should not be confused therewith.) At the saine time the indicator circuit wiper on the tens selector will engage one of the contacts 59' designated by the miniature number 04 in Fig. 11. As shown in Fig. 11, each of the contacts 59 maybe electrically connected by wires as at 52, with correspondingly numbered vertically extending busses 50, while each of the tens selector contacts 59 may be similarly connected by wires 53 to correspondingly numbered horizontally extending busses 51. Therefore the selecting operation as above describedv will result in the choosing of vertical bus number l2 and horizontal bus number O4. At the intersection of these two busses one of the terminal jacks may be located and such jack or terminal may be numbered 1204.

. It will be observed that in the arrangement of the selector contacts and in the operation of the selectors the character zero is assumed to be ten, or in other words, ten current variations are utilized 'to select .each zero character of a single designating number. This is made necessary. by reason of the fart that zero impulses cannot be utilized to actus te the selectors, for if no impulses were transn. itted,

d typical portion of the,-

ulti

actual practice unless it the selector wipers would not be advanced into engagement with any of the contacts 59V and 59'. Therefore in the contact banks 59 and 59 all contacts include the character zero are located either in the top horizontal row 0r in the right hand vertical tier. That is, such contacts preferably assume the same position in the contact banks as they would assume if the zero were the number 10. I-Iowever, in the arrangement of the numbered terminal jacks or terminals, it is of course desirable for such terminals to be numbered consecutively, tier after tier, starting from 0000, say at the upper left hand corner, and ending with 9999, say at the lower right hand corner. The manner in which the selector contacts may be connected to the terminal board busses to accomplish this arrangement is made clear from the typical connections shown in Fig. 11. In actual practice, at least upon stallation of the system, not all of the selector contacts 59 and 59 will be utilized. Therefore many of the contacts bearing higher numbers, and all of those including the character zero. might well be omitted in becomes necessary to transmit quotations for many thousands of stocks.

By thus utilizing only the contacts num-4 bered with the smaller digits the necessary number of current variations and the time required to transmit the same may be substantiallyminimiz'ed. For example, if each selecting step required 0.1 second, the entire operation of selecting one out of nine hundred stocks or other items may be accomplished in an average time of less than 0.5 seconds, including such time as is necessary for the slower acting relays to function. To secure the lowest possible average time of selection, stocks and items which are most actively dealt in in the markets should be given designating numbers including only the smaller digits, that is, such numbers as 1111, 1112, 1122, 1212.*

Thereby the minimum y possible number of current variations for selecting purposes may be used.

Selector control circuit connections The connections between the control contacts 58 of the thousands selector and the contacts 61 in the hundreds selector are shown in Fig. 5. It will be noted that each'of the ten contacts 61 is connected to all of the contacts 58 of one vertical tier of selector control contacts. The contacts 58Kl and 61 for the tens and units selectors, respectively, may be connected in a manner identical with that of the thousands and hundreds selectors, as will appear from the double set of reference nuinerals of Fig. 5.

, Transmitter Any suitable form of current variation the numbers of whichv the initial iny quotations transmitting devices, either manual, automatic or semi-automatic, maybe utilized at the central transmitting point in order to provide sustained potentials of the desired polarity interrupted by the desired undulations of current or potential drops. The elements of a suitable transmitter are schematically illustrated in Fig. 6 and may-include a ground connection 140, a source of current 141 for providing negative potentials to the lines, and a source of current 142 for a plying positive potentials to the lines. ircuit opening switches as at 143 and '144, respectively, may be provided for the sources of current 141 and 142. Double throw switches as at 145, 146,'1471and 148 mayA be provided for bringing 'each ofthe line wires L-1, L--2, L-3 andL-f4respectively, into operative relationship witheither ofthe sources of current 141 and 142,'. f In addition, each of the line wires may be provided with impulse sending switches as at sired, suitable line relays for stepping up the transmitting current and/or voltage may be provided. The various switches shown in Fig. 6 may be operated by suitablekeyboard mechanisms, the generalprinciples of which are known in the art and form no part of thisl invention, or if desired, certain of .the keys may be actuated manually and others by known forms of tape transmitting devices, or if desired, all of the transmitting switches may be controlled by a moving perforated tape in a manner hereinafter described in connection with Figs. 7 and 8. TheA principles of tape transmitting devices of this class for ordinary telegraphy, are set forth, for example, by John H. Bell in his paper entitled, Printing telegraph systems, presented February 19, 1920, and published in Volume XXXIX, Part I, of the Trans actions of the American Institute of Electrical Engineers.

In Fig. 7 two typical tape control switch and operating devices are'shown, one for operating an impulse sending switch and the other for operating a double throw or olarity selecting switch.

or operating the circuit opening switches for the polarity selection (although provided with one contact instead of two) for simplicity is not shown. A moving tape is indicated at 153, the tape being' provided with distinctive perforations representative of the 'of various items. The edges of the tape gagement witha suitable feed roller 155.

While in Fig. 7 the impulse sender for clearness is shown above the polarity selector and the showing of the tape and feed roller is repeated, it will be understood that in actual practice the impulse sender, the polarity selector, and the circuit opening switches will be located side by side and operated upon 149, 150, 151 and 152. If de-k,

The` mechanism may be perforated as at 154 for enpas from one tape and one driving mechanism. Referring to the impulse sender, a selecting pin is shown at 156 designed to engage the under side of the tape at such times as areas are passing which have no perforations. However, when a perforation in the tape occurs over the selecting pin 156, this pin is caused to rise into such perforation and causes the impulse switch as at 149 to be opened for transmitting a current variation in the form of a drop in the potential maintained on the line wire. A rotating member 157 is driven at such speed as to properly oscillate a lever 158 connected therewith by a link 159. The lever 158 has pivotallymounted thereon a thrust lever 160, carrying at one end the selecting pin 156 and designed to engage at' its other end a switch operating push rod 161, a switch arm being indicated in 162 suitably attached to the push rod 161 and is provided with a spring 163 for holding the switch as at 149 normally closed. The thrust lever 160 is normally oscillated by the action of the rotating member 157 in an elevated position where it does not contact with the push rod 161. However, when the selecting pin rises into a perforation in the tape, the thrust lever is then oscillated in the lower position where it will engage the push rod 161 for actuating the switch. Details of construction of apparatus of this type are well known and need not be here further' dep scribed.

lThe polarity selector switch mechanism may be generally similar to the impulse sender mechanism above described, and similar parts bear like reference numerals on the drawings. However, provision must here be made to operate a double throw switch. Ac- 1 cordingly, the switchk lever 162 instead of being provided with engaged by a jockey roller member as at 164 for releasably retaining the switch lever in a position to apply either a negative or a positive polarity to the line. Therefore an additional push rod as at 165 is also provided to operate the switch arm in the direction opposite from its operation when actuated upon by the push rod 161. Whenever the polarity selecting pin 156 -rises into a perforation in the tape the thrust lever 160 will engage the push rod 161, moving the switch so as to provide a negative polarity to the line. At other times when the selecting pir. engages no perforation in the tape, the thrust lever will intermittently engage the push rod 165 for maintaining the switch arm in such position as to to the line.

One possible arrangement of the perforations on the tape is shown in Fig. 8 merely by way of example. Space is provided as shown for four rows of line polarity control perforations respectively for lines L--1, L-2,.L-3 and L-4.

apply a positive polarity a retaining spring is That is, if there are the tape at these areas as the same pass over the selecting pins the positive line polarities will be then established, but whenever perforations are encountered in such areas then negative line polarities will be established. rlhe circuit opening switches 143 and 144 may be operated concurrently and controlled from a single perno perforations on Y fora-ted area designated on the drawing' as drawings impulse sender control, an'area being provided respectively for each of the lines L-1, L-2, L-3 and L`4. When perforations exist in these areas the corresponding switches 149, 150, 151 and 152 will be moved to circuit opening positions, thus causing potential drops on the corresponding lines. The functions of the succeeding groups of perforations for these various items are shown in Fig. 8 to the left offthe tape.

,Although in the system as above described provision is made for as many as ten thousand different stocks or other items, four digits to be indicated for each item, it will be understood that if provision is to be made only for a lesser number of items, for example, one thousand, one of the four selector mechanisms might readily be eliminated, the remaining three being operable over three ine wires. In .such case the hundreds digit of the stock or item quotation if desired might also b e. eliminated, since the proper hundreds digit for a particular stock or item is generally well known to the public, such practice of eliminating the hundreds, and even the tens digit being sometimes followed in the operation of the well known stock ticker system. y f

Although with a system as above described each line wire is provided with a ground return, it will be understood that a fifth and common return wire might be provided in lieu of the usel of ground connections.

Although the above described selector mechanism constitutes an adaptation of the Strowger selectors, accordingto certain phases of' the invention, many other lforms of selectors might be used with greater or lesser eitciency. For example, if desired, the all relay type of selector may be utilized, and a system embodying the use of such selectors comprises the subject of the copending application of Merton L. Haselton and Page S. 

